The invention relates generally to enhanced multi-carrier telecommunications service assurance and network testing and, in particular, to a method and apparatus for enabling multimedia services troubleshooting across multi-carrier telecommunications networks with multi-transport technologies and capabilities.
Webtone is an electronic signal that announces the immediate availability of multimedia services including telephony, web pages, electronic mail (e-mail), facsimiles, remote access to business services and any other kind of digitized information over a Public Carrier Network. Digitized information for such services are, or will become, accessible from wireline and wireless terminals. These services are supported by the fiber Synchronous Optical Network (SONET) core network with feature rich edge switching nodes that form the base for a Webtone network. A significant challenge is to provide the testing and troubleshooting mechanisms for the Webtone network for ensuring quality assurance for such services. Quality of service (QoS) is an important issue and it is one of the major hurdles to be overcome before such services gain widespread acceptance. Reliability of the network in general and availability of enhanced services are critical to Webtone success.
Webtone requires an integrated interworking of predominantly voice networks such as the Public Switched Telephone Network (PSTN), predominantly data networks such as the Internet, and narrowband/broadband integrated services digital networks (ISDN). This requirement has inspired the development of protocols such as Voice over Internet Protocol (IP), IP over Asynchronous Transfer Mode (ATM), Voice over ATM, IP over Synchronous Optical Network (SONET), etc. These developments have also promoted the concept of an Internet Phone(trademark), which is an implementation of Voice over IP. Providing QoS is an issue for voice services across an IP-based network for Internet Phones(trademark). The issue of QoS is further complicated when Voice over IP is passed to a Plain Ordinary Telephone Service (POTS) network, or vice versa. Troubleshooting multimedia services such as voice, data, video or audio in multi-carrier telecommunications networks is an issue that has not been addressed.
An expanding telecommuting workforce requires that these issues be addressed now more than ever. There is also a need to integrate services troubleshooting and QoS provisioning across multi-carrier networks to provide seamless telecommunications in a converging marketplace.
The Public Switched Telephone Network
In the Public Switched Telephone Network (PSTN), user telephone terminals and facsimile machines are connected to telephone switches. The telephone switches (which include Central Offices (COs) for wireline communications and Mobile Switching Centers (MSCs) for wireless communications) are specialized computerized switches engineered for the provision of intelligent telephone services to subscribers. The switches are interconnected through trunks, on which voice and voice-grade data are carried. The switches are also interconnected through a common channel signaling (CCS) network, typically a Signaling System No. 7 (SS7) network, which is a specialized fault-tolerant data communications network, principally used for signaling messages that control call setup and maintenance.
The PSTN is a multi-carrier network in which a plurality of interconnected and inter-working networks cooperate to deliver services. The networks in the PSTN include analogue Plan Ordinary Telephone Services (POTS) networks, narrowband (NB) Integrated Services Digital Network (ISDN), and broadband (BB) ISDN networks, based on Asynchronous Transfer Mode (ATM) transport facilities. A simple two-party call in most cases involves several telephone switches; one or more of which may be located in any one of the different networks. In combination, the switches form a complex distributed processing environment for the delivery of telecommunications services such as voice, data, video, and audio. All of the switches are presently enabled to cooperate in the delivery to customers of certain basic services, such as the provision of dial tone, ringing on a called line, and establishing connections between two or more parties.
The Internet
The Internet is a network of elements such as IP hosts, hubs, intelligent hubs, IP switches, routers, bridges, gateways, network information databases, etc. All these elements have computing abilities and utilize protocols conforming to the Open System Interconnections (OSI) model of which the Transport Control Protocol over Internet Protocol (TCP/IP) is a widespread implementation. The Internet core is provided over redundant data links.
All information transported over the Internet, whether data, video, voice, or audio is parceled into TCP/IP packets, which are routed to an intended destination. The Internet is therefore a packet switched network. There is currently no provision for deterministic routing of TCP/IP packets over the Internet and, no provision for a guaranteed throughput of TCP/IP packets. The way the packets propagate over the Internet is by a store and forward method in which TCP/IP packets are sent between the network elements making up the Internet and are buffered at each network element in a queue awaiting processing. There is no guarantee of transmission of individual packets over the Internet but there are provisions for the re-transmission of incorrectly received packets and/or packets that are lost or discarded along the way.
The inherent non-deterministic routing of TCP/IP packets over the Internet complicates troubleshooting multimedia services. There are, however, troubleshooting applications available for verifying connectivity between network elements in the Internet. These applications provide connectivity checks at the physical layer, the link layer, and the network layer. These Internet applications provide network-wide information or service-specific information.
The Internet may be accessed using dedicated connections. Nonetheless, the most common access is provided by an Internet Gateway (IP GWY) at an edge of the Internet with links to the PSTN. The IP GWYs perform protocol conversion as required, to convert time division multiplexed data from the PSTN to TCP/IP format, and vice versa.
Multi-media Webtone Services Assurance
Webtone services such as Voice over Internet (VoIP) or Data over Internet (DoIP), and many others require much more than basic calls processing. The implementation of these services requires that specialized service applications be developed to operate on equipment from different vendors, and in a multi-carrier network that includes narrowband and broadband (NB/BB) carriers. Intelligent Network Elements (INEs) such as the service control points (SCPs), Intelligent Peripherals (IPs), service Gateways (GWYs), or Service Nodes (SNs) execute service applications and provide instructions to the NB/BB wireline or wireless switches for completing service calls. Each switch is involved only in executing basic call processing, which is interrupted at standardized breakpoints when a specialized service application needs be executed. On encountering such a breakpoint, the switch issues a service request to an INE that has the service application (e.g., an SCP in a narrowband intelligent telephone network or services server for narrowband (NB) and Broadband (BB) Internet/PSTN interworking), and waits for instructions.
For some services, the INE may initiate a call on its own by instructing switches to establish necessary connections between a calling and called parties. In addition to executing the service application, other INEs can perform certain switching functions (such as bridging calls) as well as a set of specialized functions (such as playing announcements, voice recognition and text-to-speech conversation). The SCPs are typically connected to switches via an NB/BB SS7 signaling network, while Service Nodes (SNs), and Intelligent Peripherals generally communicate with the switches via an ISDN Primary or Basic Rate Interface (PRI or BRI), which combines the signaling and voice paths on a single link. An Internet Gateway (IP GWY) communicates with the switches and SNs via the NB/BB SS7 network and with the SCPs via ISDN PRI.
Although this basic infrastructure is in place, no reliable tools have been developed for isolating end-to-end service problems when the establishment of a multi-carrier service call fails.
There is therefore a need for new enhanced cost-saving services testing and troubleshooting across telecommunications networks. There is also a need for new revenue-generating services fuelled by profitability. Profitability can be increased by providing new multi-carrier services, and by reducing the cost of service troubleshooting across multi-carrier network connections.
A protocol for end-to-end services testing and troubleshooting was described in Applicant""s co-pending U.S. patent application Ser. No. 08/545,183 entitled TRAVELLING LOG FOR INTELLIGENT NETWORK TESTING, which is incorporated herein by reference. That application provides a specification of a protocol for a configurable Test Service Call with Travelling Log capability for multi-carrier intelligent networks (IN) and advance IN (AIN) telecommunications networks. It does not address the Internet/PSTN with ATM, SONET, and Ethernet technologies for multi-carrier telecommunications networks.
The invention provides methods and apparatus for enabling Webtone services testing and troubleshooting in a multi-carrier telecommunications networks which provide the services to customers or third party service providers.
The invention also provides Webtone services testing and troubleshooting for PSTN narrowband/broadband ISDN based on ATM, IP, and SONET transport technologies. The invention evolves the apparatus for enabling multimedia services testing and troubleshooting for multi-carriers within next generation networks.
The invention enables a Webtone Test Service Call with Travelling Log capability to permit network management personnel to identify faults in the network by simply launching a xe2x80x9cTest Service Call with Travelling Logxe2x80x9d. The Travelling Log provides the network management personnel with data related to the xe2x80x9chealthxe2x80x9d of each intelligent network element (INE) along the service call path. This end-to-end view of the service call path permits the network management personnel to identify any element(s) responsible for network trouble discovered by monitors or reported by customers. The Test Service Call with Travelling Log enables network management personnel to verify that Webtone originating or terminating service, or private service, is functioning correctly from a subscriber""s point of view.
As the service call-related signaling messages travel through the multi-carrier network, information is posted to the Travelling Log in accordance with the specification of the Test Service Call Parameter and Travelling Log. Network management personnel for multi-carrier services troubleshooting may use the information posted to the TravellingLog.
A Test Service Call may be initiated in a number of ways. For example, network management personnel may initiate a Test Service Call. The network management personnel use a utility, such as a graphic user interface, from a management workstation in the multi-carrier network. The utility preferably gives the network management personnel a menu of options respecting the purpose of the Test Service Call and a format and medium for presenting information gathered by the Test Service Call. The utility may be configured to automatically initialize a Test Service Call Parameter and Travelling Log for the Test Service Call. Alternatively, the utility may permit the network management personnel to manually initialize the Test Service Call Parameter and Travelling Log. A Test Service Call may also be initiated by a customer who dials a predetermined digit sequence such as xe2x80x9c*Xxe2x80x9d, as described in Applicant""s co-pending U.S. patent application Ser. No. 09/354,728 filed on Jul. 16, 1999 and entitled CUSTOMER SMART LOGGING FOR NEW TELECOMMUNICATIONS SERVICES.
As a control or data transfer (payload/bearer) signaling message associated with a Test Service Call propagates across the multi-carrier network, it may require protocol conversion at gateways or interfaces between different service delivery networks that operate under different protocols. In addition to protocol conversion, the Test Service Call Parameter and Travelling Log may require reconfiguration to ensure that appropriate information is posted to the Travelling Log by nodes in the different carrier networks.
The information posted to the Travelling Log in the control or data transfer (payload/bearer) signaling messages associated with a Test Service Call (such as signaling messages for call establishment, teardown, data transfer or query/response) may be stored and analyzed in any way that satisfies a purpose of the troubleshooting or information gathering. The type of analysis and display is dependent on the purpose of the Test Service Call and the telecommunications media available for the display.
The invention therefore provides a flexible tool for service call troubleshooting across telecommunications connections and the gathering of information in a multi-carrier telecommunications network, which enables the creation of new cost-effective troubleshooting tools as well as a delivery mechanism for many new customer services.